1. Field of the Invention
The invention relates to a planning and engineering method for a process plant, a corresponding planning and engineering software tool, a planning and engineering system for a process plant, an automation system with a planning and engineering system of this kind and to a function block compiled in accordance with the method, the software tool or with the system.
2. Description of the Related Art
To perform the engineering for the automation of a process plant, in a planning and engineering system, a corresponding software tool usually determines the structure of the process plant in a first step and a plant planning tool compiles a flow chart of the plant by linking graphical process objects. The graphic process objects represent the functional, i.e., the operator-controllable and observable facilities of the plant, such as sensors, motors, pumps, valves, metering units and regulators or even also groups of such facilities, which are more closely related, such as the drying group of a paper machine or the cooling section of a continuous casting plant. The graphical process objects are generally included as standardized blocks in libraries and are placed on a configuration interface in accordance with technical viewpoints and connected to each other via a suitable editor.
The process control system (PCS) engineering is performed via a PCS engineering tool based on function blocks containing different automation functions in the form of software. The function blocks are generally prefabricated and tested block types for repeated functions organized in process control libraries. From these block types, it is possible to compile as many instance objects with individual instances as desired and link them by means of an editor via icons on a configuration interface using drag & drop to form a function chart of the plant. Every process object has a corresponding automation function block describing the automation function of the object and which is optionally assembled from a plurality of function blocks.
When all the functions have been compiled in the function chart, the engineering system translates the function-block software into a control program (machine code) that can be read by automation devices of the plant and which is loaded into the automation devices and implemented there within the context of the control of the technical process.
In order to be able to ascertain whether the engineering for the automation was successful or in order to optimize the engineering, it is possible to define test conditions in a separate test tool and perform a simulation of at least one test under the test conditions in a simulation tool. The process, or a subprocess, is virtually simulated by simulation models of the involved process objects in a simulated environment. The simulation tool generates signals for possible events and scenarios that could occur during the operation of the plant. A simulation tool of this kind is, for example, known under the name SIMIT from Siemens AG.
The aforementioned plant planning, engineering, test and simulation tools can be formed individually or combined.
WO 2009/0898949 A1 discloses one such planning and engineering method, software tool and system for a process plant.
An automation system for a process plant is also known from US 2007/005266 A1 which, for purposes of condition monitoring of the plant, acquires process parameters and process measurements and evaluates them via correlation and statistical methods. At the same time, it is possible inter alia to calculate material and energy flows and balances.
A planning and engineering method, software tool and system for a production line supplemented by energy efficiency planning is additionally known from DE 10 2008 040440 A1. Since the power consumption of the components of the production line is known, it is possible to plan the required energy for every process in the production line as a function of the production cycle times. Different energy flows can be determined in detail from models. The energy efficiency planning can be further optimized during the operation of the production plant with reference to measurements of the cycle time and the energy consumption of the components.
In a list of priorities, the development of an energy-optimized process plant frequently comes behind the actual engineering requirements for the process. The design of the electrical fuses and cable looms for the power supplied to the plant are defined according to the statutorily prescribed maximum loads and the information on the energy consumption of the individual plant components connected in the associated data sheets. Therefore, the energy design of the plant is performed without knowledge of the consumption pattern of the plant components. As a rule, the plant operator does not know the distribution of the energy costs in the plant or only knows this distribution very imprecisely. Neither is this information available from the plant's control system. It is only possible to measure the overall energy consumption of the plant at the feed-in point via a meter. In individual cases, there are also plant components that provide consumption values during the running time of the plant. However, such components are always more expensive than the standard components that are used. To enable decentralized power monitoring, the plant can also be retrofitted with power measuring devices upstream of the respective consumers. However, such measuring devices and the installation thereof increase the overall costs of a plant.
The dynamic energy consumption of a plant is also definitively influenced by the automation. As a result, this parameter should be used as a basis for optimization during the engineering of a plant and taken into account accordingly.